[Action of estrogens on pituitary gonadotrophic function and follicular growth during diestrous in the rat (author's transl)].
LH and FSH release during the afternoon of diestrus 1 on the one hand, and the rate of follicular growth on the morning of diestrus 1 or diestrus 2, on the other hand, were studied in 4-day cyclic female rats after injection of estradiol benzoate (10 microgram, s.c.) on the morning of estrus. LH and FSH release was observed between 15.00 and 19.00 h during diestrus 1, but did not occur after an injection of pentobarbital (30 mg/kg, i.p.) in diestrus 1 at 13.30 h. No luteinization resulted from an injection of estrogen. Slowed follicular growth was observed on the morning of either diestrus 1 or diestrus 2. These results suggest the existence of a "critical period" for LH and FSH release in diestrus 1 during the afternoon. They indicate that the ovarian response to the endogenous release of gonadotropins is dependent upon the state of development of the ovarian follicles.
D000818:Animals; D004031:Diestrus / Q000187:drug effects*; D004958:Estradiol / Q000494:pharmacology*; D004971:Estrus / Q000187:drug effects*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D006065:Gonadotropins, Pituitary / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000378:metabolism; D006080:Ovarian Follicle / Q000254:growth & development*; D010053:Ovary / Q000648:ultrastructure; D010903:Pituitary Gland, Anterior / Q000502:physiology*; D011247:Pregnancy; D051381:Rats
D006065:Gonadotropins, Pituitary; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone
Action de l'oestradiol sur la fonction gonadotrope pituitaire et sur la croissance folliculaire au cours de la période dioestrale du cycle de la ratte.